INFLUENZA ATTACKS - PART ONE

(NOTE: This post/article is heavily-fuel. If you are unsure of what you are reading, it is absolutely normal. Please contact the author if you have found any inquiries about the topic. Questions are welcome]

I am sure many readers out there have heard about the report of the latest pandemic disease - Swine Flu. Over this decade alone, there are several reported cases of such diseases; started with 2003's SARS Virus, and later that year, Avian Flu, another half global pandemic disease which killed many and destroyed the poultry industry; accompanied with few others small-scaled epidemics and pandemics thereafter.

THE GLOSSARY

Before we start, here are some glossary terms you need to clarify before hand:

EPIDEMIC = "New cases of a certain disease occur in a human population, during a given period, substantially exceed what is "expected," based on recent experience. It is an infectious; may be restricted to one locale (an outbreak), more general (an epidemic) or even global (pandemic)."

PANDEMIC = "An epidemic of infectious disease that spreads through populations across a large region; for instance a continent, or even worldwide."

INFLUENZA = "An infectious disease caused by RNA viruses of the family Orthomyxoviridae (the influenza viruses), that affects birds and mammals. This term is too general to describe each of it."

AVIAN FLU = "Refers to influenza caused by viruses adapted to birds. This is particularly caused by Influenza A Virus"
SWINE FLU = "Refers to influenza cases that are caused by Orthomyxoviruses endemic to populations of pigs. This is particularly caused by Influenza C or some subtypes of Influenza A Virus."
HUMAN FLU = "Refers to influenza cases caused by Orthomyxoviridae that are endemic to human populations (as opposed to infection relying upon zoonosis). It can caused by vast variant of Influenza Virus of subtypes A, B and C."

PARAINFLUENZA = "Refers to lower respiratory tract infection, caused by a group of four distinct serotypes of single-stranded RNA viruses belonging to the paramyxovirus family."

INFLUENZA VIRUSES

In general, influenza virus derived has the following characteristics:

GROUP: V (five) due to its negative single-stranded RNA
FAMILY: Orthomyxoviridae
GENERAS: [Influenza A] - causes pandemic and attacks humans, birds and mammals; [Influenza B] - attacks humans; [Influenza C] - attacks humans and pigs; [Thogotovirus] - attacks other vertebrates and invertebrates; [Isavirus] - attacks Atlantic salmon

Due to the nature of calamity, we shall focus our attention solely into Influenza Virus A. Over the years, researches have found out that while the type B and C had caused some serious pandemic outbreaks, both types show some significant lower degree of disease nature and lower mutation ability. Looking on historical dark era in human epidemeology, incidents like Spanish Flu 1918, Asian Flu 1957 and the recent Avian Flu had pointed directly to the Influenza A Virus.

INFLUENZA VIRUS TYPE A

Influenza A viruses occur in many variants that therefore can only be identified by using a special tests that will allow viral surface proteins to be recognized. There are two types of proteins on the surface:

• Hemagglutinin (HA) component is a substance that causes red blood cell to agglutinate (clumps). Consisting of 16 subtypes, that is where you have the H1 to H16 nomenclature. HA is useful as it helps to vitus to target at specific human cells and entry of the viral genetic into them.
• Neuraminidase (NA) is a glycoside hydrolase enzymes that cuts the glycosidic linkages of neuraminic acid. Consisting of 9 subtypes, that is where you have the N1 to N9 nomenclature. NA is useful to help the virus to bud out of the host target cells and releasing its danger particles into the body.

With 16 possibles of HA and a further 9 NA, that leaves us with a possible 144 variants with further genetic alteration on a higher level will produces even more variants. The virus genetic information is stored within the 8 single RNA strands (human is DNA which is a reverse - DNA produces RNA proteins to live, while RNA proteins in virus produce proteins that alter the original DNA) capable of releasing 11 types of proteins including HA and NA.

NAMING AN INFLUENZA

An Influenza virus can be named based on the following:
Virus Type - Type A, B or C
Geographic - Origin of the discovery of a certain flu virus
Strain number -
Years of isolation -
Virus subtype - Based on its HA and NA components

** Sorry for the long lectures that leave many clueless. Again, this post is not made to confuse but should be used as merely to point out how deadly an influenza virus can be. Although in normal cases, flus can still kill about 1% of those who catches it. In a severe and deadly types; H5N1 can kills half of those who catches it.

In part two of the series, we will look at the real problem - Swine Flu.

@@(Sources from Wikipedia, CDC)